Microsoft Corp. Windows 7 and 8 operating systems are displayed for sale at a Best Buy Co. store in Orem, Utah, U.S., on Friday, Oct. 26, 2012. Microsoft Corp. introduced the biggest overhaul of its flagship Windows software in two decades, reflecting the rising stakes in its competition with Apple Inc. and Google Inc. for the loyalty of customers who are shunning personal computers and flocking to mobile devices. Photographer: George Frey/Bloomberg via Getty Images